Recently, edible insects were proposed to be promising alternative foods combining nutritional, environmental, and economic benefits. While composition of the basic nutrients of insects is quite well known, little is known about other compounds contained in them such as purines. From this point of view, raw insects were reported to belong among purine-rich foods. However, they are generally consumed after culinary processing, which is known to affect nutritional composition of foods. Therefore, we aimed to analyze the effect of culinary processing (including various combinations of boiling, roasting, blanching, baking, and oven drying) on purine (adenine, guanine, xanthine, and hypoxanthine) contents and their metabolite (uric acid) in three insects (Tenebrio molitor, Gryllus assimilis, and Acheta domesticus) fit for human consumption using RP-HPLC with UV detection. According to obtained data, boiling for 15 min significantly reduced the purine content in T. molitor but did not affect the purine levels in A. domesticus and G. assimilis. In contrast, the purine content increased in all insects after baking (especially at 220 °C). The information this study provides can help people suffering from gout interested in entomophagy to choose the best culinary treatment of insects to help prevent gout symptoms.

• Klíčová slova
• Acheta domesticus, Cooking method, Gout, Gryllus assimilis, Tenebrio molitor,
• MeSH
• dna (nemoc) * MeSH
• Gryllidae * metabolismus   MeSH
• hmyz metabolismus   MeSH
• jedlý hmyz * MeSH
• kyselina močová metabolismus   MeSH
• lidé MeSH
• puriny metabolismus   MeSH
• xanthin MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kyselina močová MeSH
• purine MeSH Prohlížeč
• puriny MeSH
• xanthin MeSH

Despite the widespread occurrence of intracellular crystalline inclusions in unicellular eukaryotes, scant attention has been paid to their composition, functions, and evolutionary origins. Using Raman microscopy, we examined >200 species from all major eukaryotic supergroups. We detected cellular crystalline inclusions in 77% species out of which 80% is composed of purines, such as anhydrous guanine (62%), guanine monohydrate (2%), uric acid (12%) and xanthine (4%). Our findings shifts the paradigm assuming predominance of calcite and oxalates. Purine crystals emerge in microorganisms in all habitats, e.g., in freshwater algae, endosymbionts of reef-building corals, deadly parasites, anaerobes in termite guts, or slime molds. Hence, purine biocrystallization is a general and ancestral eukaryotic process likely present in the last eukaryotic common ancestor (LECA) and here we propose two proteins omnipresent in eukaryotes that are likely in charge of their metabolism: hypoxanthine-guanine phosphoribosyl transferase and equilibrative nucleoside transporter. Purine crystalline inclusions are multifunctional structures representing high-capacity and rapid-turnover reserves of nitrogen and optically active elements, e.g., used in light sensing. Thus, we anticipate our work to be a starting point for further studies spanning from cell biology to global ecology, with potential applications in biotechnologies, bio-optics, or in human medicine.

• MeSH
• biomineralizace * MeSH
• Eukaryota * genetika   metabolismus   MeSH
• guanin metabolismus   MeSH
• lidé MeSH
• puriny metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• guanin MeSH
• purine MeSH Prohlížeč
• puriny MeSH

Adenylosuccinate lyase (ADSL) functions in de novo purine synthesis (DNPS) and the purine nucleotide cycle. ADSL deficiency (ADSLD) causes numerous neurodevelopmental pathologies, including microcephaly and autism spectrum disorder. ADSLD patients have normal serum purine nucleotide levels but exhibit accumulation of dephosphorylated ADSL substrates, S-Ado, and SAICAr, the latter being implicated in neurotoxic effects through unknown mechanisms. We examined the phenotypic effects of ADSL depletion in human cells and their relation to phenotypic outcomes. Using specific interventions to compensate for reduced purine levels or modulate SAICAr accumulation, we found that diminished AMP levels resulted in increased DNA damage signaling and cell cycle delays, while primary ciliogenesis was impaired specifically by loss of ADSL or administration of SAICAr. ADSL-deficient chicken and zebrafish embryos displayed impaired neurogenesis and microcephaly. Neuroprogenitor attrition in zebrafish embryos was rescued by pharmacological inhibition of DNPS, but not increased nucleotide concentration. Zebrafish also displayed phenotypes commonly linked to ciliopathies. Our results suggest that both reduced purine levels and impaired DNPS contribute to neurodevelopmental pathology in ADSLD and that defective ciliogenesis may influence the ADSLD phenotypic spectrum.

• Klíčová slova
• ADSL, ADSLD, DNA damage, SAICAR, cell biology, chicken, cilia, developmental biology, human, microcephaly, zebrafish,
• MeSH
• adenylsukcinátlyasa nedostatek   metabolismus   MeSH
• aminoimidazolkarboxamid analogy a deriváty   metabolismus   MeSH
• autistická porucha metabolismus   MeSH
• buněčné linie MeSH
• buněčný cyklus MeSH
• ciliopatie metabolismus   MeSH
• dánio pruhované metabolismus   MeSH
• fenotyp MeSH
• fosfoproteiny metabolismus   MeSH
• kur domácí metabolismus   MeSH
• lidé MeSH
• mikrocefalie metabolismus   MeSH
• neurogeneze * MeSH
• poruchy autistického spektra metabolismus   MeSH
• poruchy metabolismu purinů a pyrimidinů metabolismus   MeSH
• poškození DNA MeSH
• proteiny asociované s mikrotubuly metabolismus   MeSH
• proteiny buněčného cyklu metabolismus   MeSH
• puriny metabolismus   MeSH
• ribonukleotidy metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Intramural MeSH
• Názvy látek
• adenylsukcinátlyasa MeSH
• aminoimidazolkarboxamid MeSH
• CCP110 protein, human MeSH Prohlížeč
• fosfoproteiny MeSH
• proteiny asociované s mikrotubuly MeSH
• proteiny buněčného cyklu MeSH
• purine MeSH Prohlížeč
• puriny MeSH
• ribonukleotidy MeSH
• SAICAR MeSH Prohlížeč

In humans, GART [phosphoribosylglycinamide formyltransferase (EC 2.1.2.2) / phosphoribosylglycinamide synthetase (EC 6.3.4.13) / phosphoribosylaminoimidazole synthetase (EC 6.3.3.1)] is a trifunctional protein which catalyzes the second, third, and fifth reactions of the ten step de novo purine synthesis (DNPS) pathway. The second step of DNPS is conversion of phosphoribosylamine (5-PRA) to glycineamide ribonucleotide (GAR). 5-PRA is extremely unstable under physiological conditions and is unlikely to accumulate in the absence of GART activity. Recently, a HeLa cell line null mutant for GART was constructed via CRISPR-Cas9 mutagenesis. This cell line, crGART, is an important cellular model of DNPS inactivation that does not accumulate DNPS pathway intermediates. In the current study, we characterized the crGART versus HeLa transcriptomes in purine-supplemented and purine-depleted growth conditions. We observed multiple transcriptome changes and discuss pathways and ontologies particularly relevant to Alzheimer disease and Down syndrome. We selected the Cluster of Differentiation (CD36) gene for initial analysis based on its elevated expression in crGART versus HeLa as well as its high basal expression, high log2 value, and minimal P-value.

• MeSH
• GAR-transformylasa metabolismus   genetika   MeSH
• HeLa buňky MeSH
• lidé MeSH
• metabolom * MeSH
• puriny * metabolismus   biosyntéza   MeSH
• transkriptom * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• GAR-transformylasa MeSH
• purine MeSH Prohlížeč
• puriny * MeSH

All medically important unicellular protozoans cannot synthesize purines de novo and they entirely rely on the purine salvage pathway (PSP) for their nucleotide generation. Therefore, purine derivatives have been considered as a promising source of anti-parasitic compounds since they can act as inhibitors of the PSP enzymes or as toxic products upon their activation inside of the cell. Here, we characterized a Trypanosoma brucei enzyme involved in the salvage of adenine, the adenine phosphoribosyl transferase (APRT). We showed that its two isoforms (APRT1 and APRT2) localize partly in the cytosol and partly in the glycosomes of the bloodstream form (BSF) of the parasite. RNAi silencing of both APRT enzymes showed no major effect on the growth of BSF parasites unless grown in artificial medium with adenine as sole purine source. To add into the portfolio of inhibitors for various PSP enzymes, we designed three types of acyclic nucleotide analogs as potential APRT inhibitors. Out of fifteen inhibitors, four compounds inhibited the activity of the recombinant APRT1 with Ki in single µM values. The ANP phosphoramidate membrane-permeable prodrugs showed pronounced anti-trypanosomal activity in a cell-based assay, despite the fact that APRT enzymes are dispensable for T. brucei growth in vitro. While this suggests that the tested ANP prodrugs exert their toxicity by other means in T. brucei, the newly designed inhibitors can be further improved and explored to identify their actual target(s).

• MeSH
• adeninfosforibosyltransferasa metabolismus   MeSH
• adeninnukleotidy metabolismus   MeSH
• buněčné linie MeSH
• HeLa buňky MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nukleosidy metabolismus   MeSH
• organofosfonáty metabolismus   MeSH
• puriny metabolismus   MeSH
• Trypanosoma brucei brucei metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adeninfosforibosyltransferasa MeSH
• adeninnukleotidy MeSH
• nukleosidy MeSH
• organofosfonáty MeSH
• purine MeSH Prohlížeč
• puriny MeSH

Purine metabolism plays a ubiquitous role in the physiology of Mycobacterium tuberculosis and other mycobacteria. The purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRT) is essential for M. tuberculosis growth in vitro; however, its precise role in M. tuberculosis physiology is unclear. Membrane-permeable prodrugs of specifically designed HGPRT inhibitors arrest the growth of M. tuberculosis and represent potential new antituberculosis compounds. Here, we investigated the purine salvage pathway in the model organism Mycobacterium smegmatis Using genomic deletion analysis, we confirmed that HGPRT is the only guanine and hypoxanthine salvage enzyme in M. smegmatis but is not required for in vitro growth of this mycobacterium or survival under long-term stationary-phase conditions. We also found that prodrugs of M. tuberculosis HGPRT inhibitors displayed an unexpected antimicrobial activity against M. smegmatis that is independent of HGPRT. Our data point to a different mode of mechanism of action for these inhibitors than was originally proposed.IMPORTANCE Purine bases, released by the hydrolytic and phosphorolytic degradation of nucleic acids and nucleotides, can be salvaged and recycled. The hypoxanthine-guanine phosphoribosyltransferase (HGPRT), which catalyzes the formation of guanosine-5'-monophosphate from guanine and inosine-5'-monophosphate from hypoxanthine, represents a potential target for specific inhibitor development. Deletion of the HGPRT gene (Δhgprt) in the model organism Mycobacterium smegmatis confirmed that this enzyme is not essential for M. smegmatis growth. Prodrugs of acyclic nucleoside phosphonates (ANPs), originally designed against HGPRT from Mycobacterium tuberculosis, displayed anti-M. smegmatis activities comparable to those obtained for M. tuberculosis but also inhibited the ΔhgprtM. smegmatis strain. These results confirmed that ANPs act in M. smegmatis by a mechanism independent of HGPRT.

• Klíčová slova
• Mycobacterium smegmatis, guanine, hypoxanthine, hypoxanthine-guanine phosphoribosyltransferase, inhibitors, purine salvage pathway,
• MeSH
• antituberkulotika chemie   farmakologie   MeSH
• hypoxanthinfosforibosyltransferasa antagonisté a inhibitory   chemie   genetika   metabolismus   MeSH
• inhibitory enzymů chemie   farmakologie   MeSH
• katalýza MeSH
• metabolické sítě a dráhy MeSH
• mikrobiální viabilita MeSH
• Mycobacterium smegmatis genetika   růst a vývoj   metabolismus   MeSH
• plazmidy genetika   MeSH
• puriny metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antituberkulotika MeSH
• hypoxanthinfosforibosyltransferasa MeSH
• inhibitory enzymů MeSH
• purine MeSH Prohlížeč
• puriny MeSH

Metabolism of purine bases remains poorly understood in the pathogenic bacterium Mycobacterium tuberculosis and closely related, nonpathogenic Mycobacterium smegmatis (Msm). To gain insight into the purine metabolism in mycobacteria, we tested uptake of purine bases with a ΔpurF Msm mutant with an inactive purine de novo biosynthesis pathway and confirmed that hypoxanthine and guanine, but not xanthine, can serve as nucleotide precursors for recycling in the salvage pathway. Further, we focused on purine catabolism in wild-type (wt) Msm. We found that only xanthine and guanine could serve as a sole nitrogen source for wt Msm. These data confirm that Msm catabolism of purines is directed mainly via oxidative guanine to xanthine interconversion and not through metabolic conversion of hypoxanthine to xanthine. Our data represent the first experimental evidence confirming the use of 8-oxo-purines as a nitrogen source by Msm.

• Klíčová slova
• Guanine, Hypoxanthine, Mycobacterium smegmatis, Purine biosynthesis, Purine catabolism, Xanthine,
• MeSH
• atypické mykobakteriální infekce metabolismus   mikrobiologie   MeSH
• guanin metabolismus   MeSH
• lidé MeSH
• Mycobacterium smegmatis izolace a purifikace   metabolismus   MeSH
• puriny metabolismus   MeSH
• xanthin metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• guanin MeSH
• purine MeSH Prohlížeč
• puriny MeSH
• xanthin MeSH

We report for the first time an autosomal recessive inborn error of de novo purine synthesis (DNPS)-PAICS deficiency. We investigated two siblings from the Faroe Islands born with multiple malformations resulting in early neonatal death. Genetic analysis of affected individuals revealed a homozygous missense mutation in PAICS (c.158A>G; p.Lys53Arg) that affects the structure of the catalytic site of the bifunctional enzyme phosphoribosylaminoimidazole carboxylase (AIRC, EC 4.1.1.21)/phosphoribosylaminoimidazole succinocarboxamide synthetase (SAICARS, EC 6.3.2.6) (PAICS). The mutation reduced the catalytic activity of PAICS in heterozygous carrier and patient skin fibroblasts to approximately 50 and 10% of control levels, respectively. The catalytic activity of the corresponding recombinant enzyme protein carrying the mutation p.Lys53Arg expressed and purified from E. coli was reduced to approximately 25% of the wild-type enzyme. Similar to other two known DNPS defects-adenylosuccinate lyase deficiency and AICA-ribosiduria-the PAICS mutation prevented purinosome formation in the patient's skin fibroblasts, and this phenotype was corrected by transfection with the wild-type but not the mutated PAICS. Although aminoimidazole ribotide (AIR) and aminoimidazole riboside (AIr), the enzyme substrates that are predicted to accumulate in PAICS deficiency, were not detected in patient's fibroblasts, the cytotoxic effect of AIr on various cell lines was demonstrated. PAICS deficiency is a newly described disease that enhances our understanding of the DNPS pathway and should be considered in the diagnosis of families with recurrent spontaneous abortion or early neonatal death.

• MeSH
• adenylsukcinátlyasa nedostatek   MeSH
• autistická porucha MeSH
• fatální výsledek MeSH
• fenotyp MeSH
• karboxylyasy genetika   metabolismus   MeSH
• lidé MeSH
• mnohočetné abnormality genetika   MeSH
• mutace MeSH
• novorozenec MeSH
• peptidsynthasy genetika   metabolismus   MeSH
• perinatální smrt MeSH
• poruchy metabolismu purinů a pyrimidinů MeSH
• puriny biosyntéza   metabolismus   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Dánsko MeSH
• Názvy látek
• adenylsukcinátlyasa MeSH
• karboxylyasy MeSH
• peptidsynthasy MeSH
• phosphoribosylaminoimidazole carboxylase MeSH Prohlížeč
• phosphoribosylaminoimidazole-succinocarboxamide synthetase MeSH Prohlížeč
• puriny MeSH

We synthesized a small library of eighteen 5-substituted pyrimidine or 7-substituted 7-deazapurine nucleoside triphosphates bearing methyl, ethynyl, phenyl, benzofuryl or dibenzofuryl groups through cross-coupling reactions of nucleosides followed by triphosphorylation or through direct cross-coupling reactions of halogenated nucleoside triphosphates. We systematically studied the influence of the modification on the efficiency of T7 RNA polymerase catalyzed synthesis of modified RNA and found that modified ATP, UTP and CTP analogues bearing smaller modifications were good substrates and building blocks for the RNA synthesis even in difficult sequences incorporating multiple modified nucleotides. Bulky dibenzofuryl derivatives of ATP and GTP were not substrates for the RNA polymerase. In the case of modified GTP analogues, a modified procedure using a special promoter and GMP as initiator needed to be used to obtain efficient RNA synthesis. The T7 RNA polymerase synthesis of modified RNA can be very efficiently used for synthesis of modified RNA but the method has constraints in the sequence of the first three nucleotides of the transcript, which must contain a non-modified G in the +1 position.

• MeSH
• adenosintrifosfát analogy a deriváty   metabolismus   MeSH
• bakteriofág T7 enzymologie   MeSH
• cytidintrifosfát analogy a deriváty   metabolismus   MeSH
• DNA řízené RNA-polymerasy metabolismus   MeSH
• purinové nukleosidy chemie   metabolismus   MeSH
• puriny chemie   metabolismus   MeSH
• pyrimidinové nukleosidy chemie   metabolismus   MeSH
• RNA chemie   metabolismus   MeSH
• substrátová specifita MeSH
• uridintrifosfát analogy a deriváty   metabolismus   MeSH
• virové proteiny metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• 7-deazapurine MeSH Prohlížeč
• adenosintrifosfát MeSH
• bacteriophage T7 RNA polymerase MeSH Prohlížeč
• cytidintrifosfát MeSH
• DNA řízené RNA-polymerasy MeSH
• purinové nukleosidy MeSH
• puriny MeSH
• pyrimidinové nukleosidy MeSH
• RNA MeSH
• uridintrifosfát MeSH
• virové proteiny MeSH

Hereditary xanthinuria (type I) is caused by an inherited deficiency of the xanthine oxidorectase (XDH/XO), and is characterized by very low concentration of uric acid in blood and urine and high concentration of urinary xanthine, leading to urolithiasis. Type II results from a combined deficiency of XDH/XO and aldehyde oxidase. Patients present with hematuria, renal colic, urolithiasis or even acute renal failure. Clinical symptoms are the same for both types. In a third type, clinically distinct, sulfite oxidase activity is missing as well as XDH/XO and aldehyde oxidase. The prevalence is not known, but about 150 cases have been described so far. Hypouricemia is sometimes overlooked, that´s why we have set up the diagnostic flowchart. This consists of a) evaluation of uric acid concentrations in serum and urine with exclusion of primary renal hypouricemia, b) estimation of urinary xanthine, c) allopurinol loading test, which enables to distinguish type I and II; and finally assay of xanthine oxidoreductase activity in plasma with molecular genetic analysis. Following this diagnostic procedure we were able to find first patients with hereditary xanthinuria in our Czech population. We have detected nine cases, which is one of the largest group worldwide. Four patients were asymptomatic. All had profound hypouricemia, which was the first sign and led to referral to our department. Urinary concentrations of xanthine were in the range of 170-598 mmol/mol creatinine (normal < 30 mmol/mol creatinine). Hereditary xanthinuria is still unrecognized disorder and subjects with unexplained hypouricemia need detailed purine metabolic investigation.

• Klíčová slova
• hereditary xanthinuria, hypouricemia, xanthine oxidoreductase deficiency,
• MeSH
• aldehydoxidasa krev   nedostatek   moč   MeSH
• alopurinol metabolismus   MeSH
• diferenciální diagnóza MeSH
• dítě MeSH
• dospělí MeSH
• kyselina močová krev   moč   MeSH
• lidé MeSH
• močové kameny krev   epidemiologie   moč   MeSH
• poruchy metabolismu purinů a pyrimidinů krev   diagnóza   epidemiologie   moč   MeSH
• předškolní dítě MeSH
• puriny metabolismus   MeSH
• vrozené poruchy metabolismu krev   diagnóza   epidemiologie   moč   MeSH
• vrozené poruchy tubulárního transportu krev   epidemiologie   moč   MeSH
• xanthin krev   moč   MeSH
• xanthindehydrogenasa krev   nedostatek   metabolismus   moč   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• aldehydoxidasa MeSH
• alopurinol MeSH
• kyselina močová MeSH
• puriny MeSH
• xanthin MeSH
• xanthindehydrogenasa MeSH